Neuroethics guidance documents: principles, analysis, and implementation strategies.

Innovations in neurotechnologies have ignited conversations about ethics around the world, with implications for researchers, policymakers, and the private sector. The human rights impacts of neurotechnologies have drawn the attention of United Nations bodies; nearly 40 states are tasked with implementing the Organization for Economic Co-operation and Development's principles for responsible innovation in neurotechnology; and the United States is considering placing export controls on brain-computer interfaces. Against this backdrop, we offer the first review and analysis of neuroethics guidance documents recently issued by prominent government, private, and academic groups, focusing on commonalities and divergences in articulated goals; envisioned roles and responsibilities of different stakeholder groups; and the suggested role of the public. Drawing on lessons from the governance of other emerging technologies, we suggest implementation and evaluation strategies to guide practitioners and policymakers in operationalizing these ethical norms in research, business, and policy settings.

Cingulate dynamics track depression recovery with deep brain stimulation.

Deep brain stimulation (DBS) of the subcallosal cingulate (SCC) can provide long-term symptom relief for treatment-resistant depression (TRD)1. However, achieving stable recovery is unpredictable2, typically requiring trial-and-error stimulation adjustments due to individual recovery trajectories and subjective symptom reporting3. We currently lack objective brain-based biomarkers to guide clinical decisions by distinguishing natural transient mood fluctuations from situations requiring intervention. To address this gap, we used a new device enabling electrophysiology recording to deliver SCC DBS to ten TRD participants (ClinicalTrials.gov identifier NCT01984710). At the study endpoint of 24 weeks, 90% of participants demonstrated robust clinical response, and 70% achieved remission. Using SCC local field potentials available from six participants, we deployed an explainable artificial intelligence approach to identify SCC local field potential changes indicating the patient's current clinical state. This biomarker is distinct from transient stimulation effects, sensitive to therapeutic adjustments and accurate at capturing individual recovery states. Variable recovery trajectories are predicted by the degree of preoperative damage to the structural integrity and functional connectivity within the targeted white matter treatment network, and are matched by objective facial expression changes detected using data-driven video analysis. Our results demonstrate the utility of objective biomarkers in the management of personalized SCC DBS and provide new insight into the relationship between multifaceted (functional, anatomical and behavioural) features of TRD pathology, motivating further research into causes of variability in depression treatment.

Systemic Antitumor Immunity by PD-1/PD-L1 Inhibition Is Potentiated by Vascular-Targeted Photodynamic Therapy of Primary Tumors.

Purpose: PD-1/PD-L1 pathway inhibition is effective against advanced renal cell carcinoma, although results are variable and may depend on host factors, including the tumor microenvironment. Vascular-targeted photodynamic (VTP) therapy with the photosensitizer WST11 induces a defined local immune response, and we sought to determine whether this could potentiate the local and systemic antitumor response to PD-1 pathway inhibition.Experimental Design: Using an orthotopic Renca murine model of renal cell carcinoma that develops lung metastases, we treated primary renal tumors with either VTP alone, PD-1/PD-L1 antagonistic antibodies alone, or a combination of VTP and antibodies and then examined treatment responses, including immune infiltration in primary and metastatic sites. Modulation of PD-L1 expression by VTP in human xenograft tumors was also assessed.Results: Treatment of renal tumors with VTP in combination with systemic PD-1/PD-L1 pathway inhibition, but neither treatment alone, resulted in regression of primary tumors, prevented growth of lung metastases, and prolonged survival in a preclinical mouse model. Analysis of tumor-infiltrating lymphocytes revealed that treatment effect was associated with increased CD8+:regulatory T cell (Treg) and CD4+FoxP3-:Treg ratios in primary renal tumors and increased T-cell infiltration in sites of lung metastasis. Furthermore, PD-L1 expression is induced following VTP treatment of human renal cell carcinoma xenografts.Conclusions: Our results demonstrate a role for local immune modulation with VTP in combination with PD-1/PD-L1 pathway inhibition for generation of potent local and systemic antitumor responses. This combined modality strategy may be an effective therapy in cancers resistant to PD-1/PD-L1 pathway inhibition alone. Clin Cancer Res; 24(3); 592-9. ©2017 AACR.

Drug development for noncastrate prostate cancer in a changed therapeutic landscape.

The unprecedented progress in the treatment of metastatic castration-resistant prostate cancer is only beginning to be realized in patients with noncastrate disease. This slow progress in part reflects the use of trial objectives focused on time-to-event end points, such as time to metastasis and overall survival, which require long follow-up durations and large sample sizes, and has been further delayed by the use of approved therapies that are effective at the time of progression. Our central hypotheses are that progress can be accelerated, and that outcomes can be improved by shifting trial objectives to response measures occurring early that solely reflect the effects of the treatment. To test these hypotheses, a continuously enrolling multi-arm, multi-stage randomized trial design, analogous to that used in the STAMPEDE trial, has been developed. Eligibility is focused on patients with incurable disease or those with a high risk of death with any form of monotherapy alone. The primary objective is to eliminate all disease using a multimodality treatment strategy. End points include pathological complete response and an undetectable level of serum prostate-specific antigen, with recovery of serum testosterone levels. Both are binary, objective, and provide an early, quantitative indication of efficacy.

Drug development for noncastrate prostate cancer in a changed therapeutic landscape.

This corrects the article DOI: 10.1038/nrclinonc.2017.160.

A Pilot Study of a Multimodal Treatment Paradigm to Accelerate Drug Evaluations in Early-stage Metastatic Prostate Cancer.

OBJECTIVE: To evaluate a multimodal strategy aimed at treating all sites of disease that provides a rapid readout of success or failure in men presenting with non-castrate metastatic prostate cancers that are incurable with single modality therapy. MATERIALS AND METHODS: Twenty selected men with oligometastatic M1a (extrapelvic nodal disease) or M1b (bone disease) at diagnosis were treated using a multimodal approach that included androgen deprivation, radical prostatectomy plus pelvic lymphadenectomy (retroperitoneal lymphadenectomy in the presence of clinically positive retroperitoneal nodes), and stereotactic body radiotherapy to osseous disease or the primary site. Outcomes of each treatment were assessed sequentially. Androgen deprivation was discontinued in responding patients. The primary end point was an undetectable prostate-specific antigen (PSA) after testosterone recovery. The goal was to eliminate all detectable disease. RESULTS: Each treatment modality contributed to the outcome: 95% of the cohort achieved an undetectable PSA with multimodal treatment, including 25% of patients after androgen deprivation alone and an additional 50% and 20% after surgery and radiotherapy, respectively. Overall, 20% of patients (95% confidence interval: 3%-38%) achieved the primary end point, which persisted for 5, 6, 27+ , and 46+ months. All patients meeting the primary end point had been classified with M1b disease at presentation. CONCLUSION: A sequentially applied multimodal treatment strategy can eliminate detectable disease in selected patients with metastatic spread at diagnosis. The end point of undetectable PSA after testosterone recovery should be considered when evaluating new approaches to rapidly set priorities for large-scale testing in early metastatic disease states and to shift the paradigm from palliation to cure.

Late Relapse of Testicular Germ Cell Tumors.

Germ cell tumors of the testis have an overall survival rate greater than 90% as a result of a successful multidisciplinary approach to management. Late relapse affects a subset of patients however, and tends to be chemorefractory and the overall prognosis is poor. Surgery is the mainstay in management of late relapse but salvage chemotherapy can be successful. In this review, the clinical presentation and detection of late relapse, clinical outcomes, and predictors of survival in late relapse and the importance of a multidisciplinary treatment approach for successful management of late relapse are discussed.

Bladder biopsy of normal-appearing mucosa is not helpful in patients with unexplained positive cytology after nonmuscle invasive bladder cancer.

PURPOSE: Malignant voided cytology with normal endoscopic evaluation represents a diagnostic and therapeutic challenge in many patients with a history of nonmuscle invasive bladder cancer. Bladder biopsy is often advised but its efficacy is unclear. We evaluated the usefulness of bladder biopsy in patients with unexplained positive cytology and describe recurrence patterns in this unique patient subset. MATERIALS AND METHODS: From an institutional database we retrospectively identified patients with a history of nonmuscle invasive bladder cancer and surveillance cystoscopy from 2008 to 2012 who had malignant voided urine cytology but normal cystoscopy. Patients underwent systematic bladder biopsy or cystoscopic surveillance and were followed for recurrence and progression. RESULTS: Of 444 patients 343 were followed with surveillance only and 101 underwent a total of 118 biopsies of normal-appearing bladder mucosa. Three biopsies (2.5%) showed carcinoma in situ and none revealed invasive carcinoma. During the median 32-month followup recurrence developed in the bladder in 194 patients (44%), in the upper tract in 24 (5%) and in the prostatic urethra in 5 (1%) while 219 (49%) had no recurrence. A previous diagnosis of upper tract urothelial carcinoma and a history of bacillus Calmette-Guérin treatment were associated with an increased recurrence risk on multivariate analysis. Recurrence rates and patterns were similar in the biopsy and surveillance groups. CONCLUSIONS: Patients with malignant cytology despite normal cystoscopy have a high recurrence rate. Biopsy of normal-appearing bladder mucosa in this setting is rarely positive and does not alter the recurrence pattern.

Factors associated with reduction in use of neoadjuvant androgen suppression therapy before radical prostatectomy.

OBJECTIVE: To determine whether the prescribing patterns for nonindicated androgen suppression therapy (AST), using neoadjuvant AST as the model, changed according to the prevailing clinical evidence, changes in reimbursement, or evidence of increased harm from treatment. MATERIALS AND METHODS: We identified 34,976 men with prostate cancer who had undergone radical prostatectomy within 12 months of diagnosis from the Surveillance, Epidemiology, and End Results-Medicare data set (1992-2007), and their clinical and demographic parameters were assessed. We measured the Medicare claims for receipt of AST before radical prostatectomy and calculated the annual rates of neoadjuvant AST, which were adjusted for confounding variables using multivariate logistic regression analysis, and compared them with the prevailing published clinical data on the outcomes of neoadjuvant AST, changes in reimbursement, or published data on clinical harm from treatment. RESULTS: The use of neoadjuvant AST increased from 7.8% in 1992 to a peak of 17.6% in 1996 and then decreased steadily to 4.6% in 2007. This rate change was significant on multivariate regression analysis, with a single join point in 1996 (P <.001), and corresponded to published data showing improved surgical margin rates and pathologic downstaging in the early 1990s and data showing no improvement in disease recurrence or overall survival beginning in 1997. Changes in reimbursement and evidence of harm from AST were not associated with the decreased use of neoadjuvant AST. CONCLUSION: Using neoadjuvant AST as the model for the nonindicated use of AST, physicians reduced AST use in response to high-level evidence showing a lack of benefit, despite the high reimbursement. This suggests that physicians adapt to emerging evidence and use evidence-based practice.

Prostate cancer screening: issues and controversies.

Prostate cancer is the second leading cause of cancer death among men. Because it has been thought that identifying the disease earlier leads to better outcomes, there has been a great deal of interest in screening for the disease. Since the late 1980s, testing for elevated prostate-specific antigen (PSA) levels in blood has been the most prominent screening tool. Despite widespread adoption of PSA testing, however, it remains controversial. It has been shown that elevated PSA levels do not always indicate cancer and low PSA levels do not ensure that cancer is absent. In addition, there has been conflicting evidence about whether definitive treatment of prostate cancer is always indicated. As a result of the conflicting evidence on the efficacy of PSA testing as a screening tool and the necessity of treatment of prostate cancer in all cases, national organizations have issued various guidelines for screening. Thus, the decision to screen or not to screen remains in the court of the individual patient and physician. This article reviews the current thinking about PSA testing, highlights relevant research findings, and discusses possible changes to screening and treatment that may appear in the near future.

Multipotent adult progenitor cells can suppress graft-versus-host disease via prostaglandin E2 synthesis and only if localized to sites of allopriming.

Multipotent adult progenitor cells (MAPCs) are nonhematopoietic stem cells capable of giving rise to a broad range of tissue cells. As such, MAPCs hold promise for tissue injury repair after transplant. In vitro, MAPCs potently suppressed allogeneic T-cell activation and proliferation in a dose-dependent, cell contact-independent, and T-regulatory cell-independent manner. Suppression occurred primarily through prostaglandin E(2) synthesis in MAPCs, which resulted in decreased proinflammatory cytokine production. When given systemically, MAPCs did not home to sites of allopriming and did not suppress graft-versus-host disease (GVHD). To ensure that MAPCs would colocalize with donor T cells, MAPCs were injected directly into the spleen at bone marrow transplantation. MAPCs limited donor T-cell proliferation and GVHD-induced injury via prostaglandin E(2) synthesis in vivo. Moreover, MAPCs altered the balance away from positive and toward inhibitory costimulatory pathway expression in splenic T cells and antigen-presenting cells. These findings are the first to describe the immunosuppressive capacity and mechanism of MAPC-induced suppression of T-cell alloresponses and illustrate the requirement for MAPC colocalization to sites of initial donor T-cell activation for GVHD inhibition. Such data have implications for the use of allogeneic MAPCs and possibly other immunomodulatory nonhematopoietic stem cells for preventing GVHD in the clinic.

Outgrowth of CD4low/negCD25+ T cells with suppressor function in CD4+CD25+ T cell cultures upon polyclonal stimulation ex vivo.

CD4(+)CD25(+) regulatory T cells (Tregs) play an essential role in controlling autoimmunity and allograft rejection. Several ex vivo activation and expansion protocols have been developed to amplify cell numbers and suppressor function of murine and human Tregs. We demonstrate in this study that ex vivo activation and expansion of murine Tregs resulted in an enrichment of a CD4(low/neg)CD25(+) T cell population that was more than 20-fold more potent than expanded conventional Tregs in suppressing an in vitro CD4(+)CD25(-) T cell response to allo-Ag. The generation of CD4(low/neg)CD25(+) T cells was independent of the presence of Tregs in the culture, and suppressor function was acquired only after activation and expansion. CD4(low/neg)CD25(+) T cells expressed either an alphabeta or gammadelta TCR, had an activated phenotype, and did not express the transcription factor FoxP3. Despite expressing the cell surface Ags lymphocyte activation gene-3 (CD223) and CD103, neither was essential for suppressor cell function. Suppression by CD4(low/neg)CD25(+) T cells was prevented by a semipermeable membrane and was independent of IL-10 and TGF-beta. In summary, we describe in this study CD4(low/neg)CD25(+) FoxP3(neg) T cells with highly potent suppressor cell function derived from cultures of an enriched population of CD4(+)CD25(+) T cells that may contribute to the suppressor activity of ex vivo expanded bone fide Tregs.

Elevation of intracellular cyclic AMP in alloreactive CD4(+) T Cells induces alloantigen-specific tolerance that can prevent GVHD lethality in vivo.

Cyclic AMP (cAMP) is an important negative regulator of T cell activation, and an increased level of cAMP is associated with T cell hyporesponsiveness in vitro. We sought to determine whether elevating intracellular cAMP levels ex vivo in alloreactive T cells during primary mixed lymphocyte reactions (MLR) is sufficient to induce alloantigen-specific tolerance and prevent graft-versus-host disease (GVHD). Primary MLRs were treated with exogenous (8)Br-cAMP and IBMX, a compound that increases intracellular cAMP levels by inhibition of phosphodiesterases. T cell proliferation and IL-2 responsiveness in the treated primary MLR cultures were greatly reduced, and viable T cells recovered on day 8 also had impaired responses to restimulation with alloantigen compared to control-treated cells, but without an impairment to nonspecific mitogens. Labeling experiments showed that cAMP/IBMX inhibited alloreactive T cell proliferation by limiting the number of cell divisions, increasing susceptibility to apoptosis, and rendering nondeleted alloreactive T cells hyporesponsive to alloantigen restimulation. cAMP/IBMX-treated CD4(+) T cells had a markedly reduced capacity for GVHD lethality in major histocompatibility complex class II disparate recipients, but maintained the capacity to mediate other CD4(+) T cell responses in vivo. Thus, our results provide the first preclinical evidence of using cAMP-elevating pharmaceutical reagents to achieve long-term alloantigen-specific T cell tolerance that is sufficient to prevent GVHD.

Hematopoietic reconstitution by multipotent adult progenitor cells: precursors to long-term hematopoietic stem cells.

For decades, in vitro expansion of transplantable hematopoietic stem cells (HSCs) has been an elusive goal. Here, we demonstrate that multipotent adult progenitor cells (MAPCs), isolated from green fluorescent protein (GFP)-transgenic mice and expanded in vitro for >40-80 population doublings, are capable of multilineage hematopoietic engraftment of immunodeficient mice. Among MAPC-derived GFP+CD45.2+ cells in the bone marrow of engrafted mice, HSCs were present that could radioprotect and reconstitute multilineage hematopoiesis in secondary and tertiary recipients, as well as myeloid and lymphoid hematopoietic progenitor subsets and functional GFP+ MAPC-derived lymphocytes that were functional. Although hematopoietic contribution by MAPCs was comparable to control KTLS HSCs, approximately 10(3)-fold more MAPCs were required for efficient engraftment. Because GFP+ host-derived CD45.1+ cells were not observed, fusion is not likely to account for the generation of HSCs by MAPCs.

Host factors that impact the biodistribution and persistence of multipotent adult progenitor cells.

Multipotent adult progenitor cells (MAPCs) are marrow-derived pluripotent stem cells with a broad differentiation potential. We sought to identify factors that affect adoptively transferred MAPCs. In vitro, MAPCs expressed low levels of major histocompatibility complex (MHC) antigens, failed to stimulate CD4(+) and CD8(+) T-cell alloresponses, and were targets of NK cytolysis. To study in vivo biodistribution, we labeled MAPCs with luciferase for sequential quantification of bioluminescence and DsRed2 for immunohistochemical analysis. C57BL /6 MAPCs were infused intravenously into C57BL /6, Rag-2(-/-) (T- and B-cell-deficient), and Rag-2(-/-)/IL-2Rgamma(c)(-/-) (T-, B-, and NK-cell-deficient) mice. In C57BL /6 mice, MAPCs were transiently detected only in the chest compared with long-term persistence in T- and B-cell-deficient mice. NK depletion reduced MAPC elimination. Because the lungs were the major uptake site after intravenous injection, intra-arterial injections were tested and found to result in more widespread biodistribution. Widespread MAPC biodistribution and long-term persistence were seen in irradiated recipients given allogeneic marrow and MAPCs; such MAPCs expressed MHC class I antigens in tissues. Our data indicate that the biodistribution and persistence of reporter gene-labeled MAPCs are maximized after intra-arterial delivery or host irradiation and that T cells, B cells, and NK cells contribute to in vivo MAPC rejection.

Inhibition of acute graft-versus-host disease with retention of graft-versus-tumor effects by the proteasome inhibitor bortezomib.

Graft-versus-host disease (GVHD) represents a major hurdle impeding the efficacy of allogeneic bone marrow transplantation (BMT). Bortezomib is a proteasome inhibitor that was recently approved for treatment of myeloma. We found that bortezomib potently inhibited in vitro mixed lymphocyte responses and promoted the apoptosis of alloreactive T cells. Bortezomib given at the time of allogeneic BMT in mice resulted in significant protection from acute GVHD. Reductions in GVHD-associated parameters and biological evidence of proteasome inhibition were observed with this regimen but with no adverse effects on long-term donor reconstitution. Assessment of graft-versus-tumor responses in advanced leukemia-bearing mice demonstrated that only the combination of allogeneic BMT and T cells with bortezomib promoted significant increases in survival. Increased cytotoxic T cell killing of the tumor was also observed. Thus, the combination of proteasome inhibition with selective immune attack can markedly increase the efficacy of BMT in cancer.

IL-10 and TGF-beta induce alloreactive CD4+CD25- T cells to acquire regulatory cell function.

We previously reported that interleukin-10 (IL-10) and transforming growth factor (TGF)-beta treatment of primary mixed lymphocyte reaction (MLR) cultures resulted in secondary alloantigen-specific hyporesponsiveness and protection from graft-versus-host disease (GVHD) lethality. Here, we report that CD4+ T cells recovered from the IL-10- and TGF-beta-treated primary MLR cultures have immunoregulatory function. Tolerized cells significantly inhibited proliferation of naive alloreactive CD4+ T cells in a primary MLR. Inhibition of the naive alloresponse was observed with as few as 1 tolerized cell to 10 naive responder cells. Tolerized cells were able to significantly reduce GVHD lethality when injected with naive alloreactive CD4+ T cells into major histocombatibility class (MHC) II disparate recipients. Rigorous CD25 depletion of the primary MLR had no effect on generation of a regulatory capacity, suggesting that the regulatory cells likely originated from CD4+CD25- T cells. Immune suppression was mediated independently of IL-10 and TGF-beta production, as neutralizing antibodies for IL-10, IL-10R, and TGF-beta were unable to revert suppression, and IL-10- deficient CD4+ T cells were able to mediate in vitro and in vivo suppression. The generation of immunoregulatory cells from a CD4+CD25- population during tolerization with IL-10 and TGF-beta provides an additional mechanism to prevent GVHD lethality by T cells that may escape full tolerance induction.